1. Field of the Invention
The present invention relates to a grommet to be mountable on a wiring harness to be arranged through a panel of an automotive vehicle and is particularly designed to improve the water preventing property thereof.
2. Description of the Prior Art
A prior art grommet that is mountable on a wiring harness W/H to be arranged between a passenger compartment and a door of an automotive vehicle is shown in FIGS. 4-6.
As shown in FIG. 5, a grommet 100 includes an integral assembly having a narrow tube portion 40. A tapered tube portion 41 is continuous with one end of the narrow tube portion 40, and has a diameter of which increases so as to be conically configured. A locking recess 41a is formed in the outer surface of a larger side of the tapered tube portion 41. A corrugated tube portion 42 is continuous with the tapered tube portion 41, and a tapered tube portion 43 is continuous with the corrugated tube portion 42. A locking recess 43a is formed in the outer surface of the tapered tube portion 43. The tube portions 40, 41 and the locking recess 41a are to be arranged at a passenger compartment side, whereas the tapered tube portions 43 and the locking recess 43a are to be arranged at a door side.
The wiring harness W/H is passed through a hollow portion of the grommet 100. The locking recess 41a is lockingly engaged with a through hole 44a formed in an outer panel 44 and the narrow tube portion 40 is passed through a through hole 45a formed in an inner panel 45. The locking recess 43a is lockingly engaged with a through hole 46a formed in a door panel 46. In this way, the wiring harness W/H can be arranged between the passenger compartment and the door.
The entrance of water through the through holes typically is prevented by the grommet 100. However, there are some cases where the entrance of water cannot be securely prevented by the grommet 100. In other words, water may enter through a fine clearance between the locking recesses 41a, 43a of the grommet 100 and the through holes 44a, 46a. In this case, the water 47 having entered the door can be discharged outside through water discharge holes formed in the bottom of the interior of the door D shown in FIG. 4. However, as shown in FIG. 6, water 48 may enter the passenger compartment inside the inner panel 45 along the surfaces of the tapered tube portion 41 and the narrow tube portion 40 of the grommet 100 and the surface of the wiring harness W/H. Thus, there is a possibility that such water 48 may cause a short circuit of electrodes connected with a connector 49 at the leading end of the wiring harness W/H, thereby adversely affecting an electric circuit.
In view of the above problems, an object of the present invention is to provide a grommet which can prevent water from entering a passenger compartment through a fine clearance between locking recesses of the grommet and the edges of through holes.